摘要
以郑州地铁3号线某区间盾构隧道切桩施工为工程背景,通过数值模拟分析盾构隧道切桩施工过程中残桩对地表沉降和管片力学性能的影响。基于Mohr-Coulomb屈服准则和混凝土损伤塑性模型(CDP模型)构建三维数值模型,研究无残桩和有残桩两种工况下的地表沉降和隧道管片受力情况。结果表明:残桩存在时地表沉降最大值出现在残桩位置,较无残桩时增大3.2 mm,需进行土体注浆加固以减小沉降。管片在残桩自重作用下未产生明显损伤,但考虑后期地铁列车运行产生的振动影响,在残桩产生较大主动沉降时,管片上部易出现拉伸损伤。因此,建议对残桩周边土体进行加固,以约束残桩竖向位移,确保隧道结构安全。
Taking the pile cutting project in a shield-driven running tunnel of Zhengzhou Metro Line 3 as the engineering background,this study employs numerical simulations to analyze the influence of residual pile on surface settlement and the mechanical properties of tunnel segments during the pile cutting process in the shield tunnel,A numerical model is constructed based on the Mohr-Coulomb yield criterion and the Concrete Damaged Plasticity Model(CDP model)to investigate the surface settlement and tunnel segment stress conditions under two scenarios:without and with residual pile.The findings reveal that when residual pile is present,the maximum surface settlement occurs at the location of residual pile,resulting in a 3.2 mm increase compared to the absence of residual pile,necessitating soil grouting reinforcement to mitigate setlement.The tunnel segments sustain notable damage under the self-weight of the residual pile.However,considering the vibrations induced by subway trains during the subsequent operation stage,when substantial active settlement occurs in the residual pile,the upper portion of the segments is prone to tensile damage.Consequently,it is recommended to reinforce the soil surounding the residual pile to constrain the vertical displacement of residual pile,thereby ensuring the structural safety of the tunnel.
作者
徐平
左思贤
XU Ping;ZUO Sixian(School of Water Conservancy and Transportation,Zhengzhou University,Zhengzhou 450001;School of Civil Engineering,Zhengzhou College of Finance and Economics,Zhengzhou 450001)
出处
《现代隧道技术》
CSCD
北大核心
2024年第S01期509-515,共7页
Modern Tunnelling Technology
基金
河南省科技攻关项目(242102240019)
关键词
残桩
盾构隧道
地表沉降
管片损伤
注浆加固
Residual pile
Shield tunnel
Surface settlement
Segment damage
Grouting reinforcement
作者简介
徐平(1977-),男,博士,教授,博士生导师,主要从事盾构施工风险控制与轨道减振隔振方面的研究工作,E-mail:Plian127@163.com.
